2020 Ram ProMaster: Transmission & Axle Gear Ratios

Transmission Gear Ratios

The 2020 Ram ProMaster comes equipped with a single transmission option, the Chrysler 62TE 6-speed automatic transaxle. This transmission is a well-regarded unit known for its smooth shifting and reliability in demanding commercial applications.

Chrysler 62TE 6-Speed Automatic

Available Axle Ratios

Unlike traditional body-on-frame vans or trucks, the front-wheel-drive ProMaster utilizes a final drive ratio within its transaxle, rather than a separate rear axle differential. For 2020, Ram simplified the powertrain offerings, providing one standard final drive ratio that is used across all models and configurations.

This single ratio is designed to offer a good balance between acceleration and fuel economy. It provides sufficient power for city driving and hauling moderate loads without sacrificing too much efficiency at highway speeds.

How to Identify Your Axle Ratio

Since the 2020 ProMaster comes with a standard 3.86:1 final drive ratio, there is typically no need to identify different options. However, you can still confirm your vehicle's build specifications in a few ways:

• VIN Decoder: Use an online VIN decoder to get a full build sheet for your specific ProMaster. This will list the "DMU" axle ratio code among many other features.
• Build Sheet: Some vehicles may have a build sheet included with the original paperwork from the dealership. Look for the sales code "DMU" under the "Optional Equipment" or "Standard Equipment" sections.
• Dealership Inquiry: Any Ram dealership can pull up your vehicle's original build configuration using your VIN, confirming the standard equipment it was built with.

Towing vs. MPG Impact

The relationship between axle ratios and performance is a fundamental aspect of vehicle dynamics. A "numerically higher" ratio (like 4.10:1) is often called a "shorter" gear. It multiplies engine torque more effectively, resulting in better acceleration and increased towing capacity. The trade-off is that the engine must run at higher RPMs at a given speed, which increases fuel consumption.

Conversely, a "numerically lower" ratio (like 3.21:1) is a "taller" gear. It requires fewer engine revolutions to maintain highway speed, leading to better fuel economy. The compromise is reduced towing capability and slower acceleration from a stop.

The 3.86:1 final drive ratio in the ProMaster is a compromise between these two extremes. It provides the low-end grunt needed to get a heavy van moving while still allowing for relatively efficient cruising in the overdrive 6th gear (0.690:1). This makes it a versatile choice for the varied demands of commercial van use, from stop-and-go delivery routes to longer highway journeys.

Common Issues

The 62TE transmission is generally considered robust, but like any component, it is not without potential issues, especially under heavy commercial use. Some reported concerns include:

• Solenoid Pack Failure: The transmission's solenoid pack can sometimes fail, leading to harsh shifting, getting stuck in one gear (limp mode), or a check engine light. This is a relatively common wear item on higher-mileage vehicles.
• Torque Converter Problems: Issues with the torque converter can manifest as shuddering or vibration, particularly under light acceleration or when shifting. In some cases, this can be resolved with a fluid and filter change, but may require converter replacement.
• Transmission Cooler Lines: Some owners have reported leaks from the transmission cooler lines, which can lead to fluid loss and subsequent transmission damage if not addressed promptly. Regular inspection of these lines for corrosion or leaks is recommended.

It is important to note that many of these issues can be mitigated or prevented with regular maintenance, including scheduled transmission fluid and filter changes as recommended by Ram.

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